21403 ZIP Code, Annapolis, MD

21403 is a ZIP code in Annapolis, Maryland in Anne Arundel County. It covers 9.3 square miles of land. The closest ZIP codes are 21037, 21402 and 21401. 32,681 people live here in 14,359 households. At about 3,526 people per square mile it has suburban density, and owners and renters are mixed (69% own). Median household income is $123,329, above the Maryland median of $103,678; the median age is 45.3, older than most ZIP codes.

Quick facts

Key figures

MeasureValue
Residents32,681
Households14,359
Median household income$123,329
Income per person$78,015
Median age45.3
Homeowners69.1%
Median home value$582,500
Median rent$1,942
Bachelor's degree or higher56.4%
Average commute (minutes)31.4
Households with kids under 1823.4%
Moved in the past year11.2%
Below the poverty line5.8%
Broadband internet95.8%
Speak a non-English language at home14.2%

Household income

% of householdsValue
<$10K2.7%
$10–15K0.7%
$15–25K4.9%
$25–35K3.3%
$35–50K4.7%
$50–75K11.7%
$75–100K11.5%
$100–150K18.0%
$150–200K13.0%
$200K+29.7%

Age

% of all residentsValue
<1011.1%
10–199.3%
20–245.2%
25–3410.9%
35–4413.3%
45–5412.1%
55–6415.8%
65–7413.2%
75+8.9%

Tenure

% of housing unitsValue
Owned, with mortgage45.7%
Owned outright18.9%
Rented28.4%
Vacant7.0%

Type of building

% of housing unitsValue
Detached house51.7%
Townhome16.5%
2–4 units3.1%
5–19 units20.8%
20+ units7.3%
Mobile / other0.4%

Businesses in 21403

678 business establishments with 6,546 employees (ZIP Codes Business Patterns 2023).

EDDM carrier routes

21403 has 28 USPS carrier routes with 14,173 residential and 603 business mailboxes. Open the EDDM route map.

Carrier routes in 21403

21403 has 28 USPS carrier routes (22 city (C), 6 rural (R)) with 14,173 residential and 603 business mailboxes. Routes range from 291 homes (C011) to 742 homes (C032); the median route has 527 homes. The Census counted 14,359 households in 21403 (2020–2024 average); USPS counts current mailboxes, including new and vacant homes.

Homes per routeRoutes
1–2490
250–49913
500–74915
750–9990
1,000–1,4990
1,500+0

Best routes in 21403 for…

Most businesses

For B2B offers: office supplies, cleaning, IT, catering and commercial services.

  1. Route C011 — USPS business mailboxes 174, 291 homes
  2. Route R021 — USPS business mailboxes 69, 604 homes
  3. Route C007 — USPS business mailboxes 65, 337 homes
  4. Route C015 — USPS business mailboxes 55, 410 homes
  5. Route C009 — USPS business mailboxes 30, 533 homes

Select these 5 routes on the route map

Every carrier route in 21403

RouteTypeHomesBusinessesEst. median incomeEst. ownersEst. families with kidsEst. moved in past year
C001City4203$155,018———
C004City3680$113,153———
C006City4264$96,656———
C007City33765$164,277———
C008City6392$108,819———
C009City53330$67,693———
C010City31125$149,346———
C011City291174$164,277———
C012City4361$108,819———
C013City5302$95,387———
C014City62612$96,656———
C015City41055$101,407———
C017City3731$108,819———
C018City66619$108,819———
C020City4465$200,001+———
C023City6522$108,819———
C024City6595$101,748———
C025City38523$191,738———
C028City47923$142,125———
C029City54327$128,493———
C030City45320$95,387———
C032City7423$153,156———
R003Rural5534$158,231———
R007Rural6430$174,329———
R008Rural58318$49,293———
R020Rural5423$108,819———
R021Rural60469$153,156———
R024Rural5238$174,329———

Income, owners, families and movers are estimates for each route (how we estimate them); mailbox counts are current USPS figures. Open 21403 on the EDDM route map.

How route demographics are estimated

Mailbox counts come from USPS; demographics are estimates

The number of homes and businesses on each carrier route is the current USPS EDDM count. The Census Bureau does not publish figures for carrier routes, so income, homeownership, ages, families, movers and housing age on a route are EDDM2GO estimates built from Census block groups (neighborhood areas of roughly 600 to 3,000 people).

How a route gets its figures: the block-group length-share method

We trace each route's streets every 25 meters and record which block group each stretch falls in. The route's homes are spread along its streets in proportion to length, so a route with 60% of its street length in one block group is assumed to have 60% of its homes there. Each block group then contributes its Census counts in proportion to the share of its housing units that sit on the route (capped at the whole block group). Medians are recalculated from the combined income, home-value and age brackets, the way the Census Bureau computes them, not averaged.

Margins of error

Census survey figures carry a margin of error at 90% confidence; we carry it through the calculation and show it as ±. Our margins treat the route-to-block-group split as exact, so the real uncertainty is larger. Routes with fewer than 100 estimated households, large margins, or streets we could not place are flagged.

Different years

USPS mailbox counts are current. Census figures are 5-year averages for 2020–2024, so a new subdivision may have more homes on the route today than the Census counted. Use the route figures to compare routes with each other, not as an exact head count.

Why some routes show identical figures

Two routes that run through the same block group get the same percentages and medians, because the Census publishes one set of figures for the whole block group. Their mailbox counts still differ, and those are exact.

Route and mailbox counts: USPS EDDM route data. Route demographics: EDDM2GO estimates from U.S. Census Bureau American Community Survey 5-year block-group data (2020–2024) and 2024 cartographic block-group boundaries. This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.

Nearby ZIP codes

Areas that include 21403

Where it ranks

Mail every home in 21403

Route counts on this page price as Full Service 6.5 × 9 postcards: we print, bundle by carrier route and hand the mailing to USPS. Prefer to take it to the Post Office yourself? Print only costs less and you pay postage at drop-off.

EDDM guides

ZIP code statistics describe the Census ZIP Code Tabulation Area (ZCTA) 21403, which approximates the USPS ZIP code area. Census figures: American Community Survey 5-year estimates, 2020–2024.

Frequently asked questions

What city is 21403 in?
21403 is a Annapolis, MD mailing address. By land area, 63% lies inside Annapolis Neck and 37% lies inside Annapolis.
What county is 21403 in?
21403 is in Anne Arundel County.
What is the population of 21403?
About 32,681 people (±1,770), according to the Census Bureau's American Community Survey 5-year estimates for 2020–2024. The 2020 Census counted 31,521.
What is the median household income in 21403?
$123,329 (±$10,213), compared with $103,678 for Maryland as a whole. Half the households in the ZIP code earn more and half earn less.
How many carrier routes and mailboxes are in 21403?
28 USPS carrier routes with 14,173 residential and 603 business mailboxes (14,776 in all), from the route data stored by EDDM2GO. An EDDM mailing can target any combination of these routes.
What ZIP codes are near 21403?
The closest, measured center to center: 21037 (3.3 mi, Mayo), 21402 (3.4 mi, Naval Academy), 21401 (4.6 mi, Parole), 21140 (5.3 mi, Riva), 21409 (5.8 mi, Cape St. Claire) and 21405 (6.7 mi).

This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.